Viewing archive of Tuesday, 26 September 2023
Solar activity report
Report of Solar-Geophysical Activity 2023 Sep 26 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 269 Issued at 2200Z on 26 Sep 2023IA. Analysis of Solar Active Regions and Activity from 25-2100Z to 26-2100Z Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C5 event observed at
26/0428Z from Region 3445 (S13W23). There are currently 10 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with
a chance for M-class flares and a slight chance for an X-class flare on
days one, two, and three (27 Sep, 28 Sep, 29 Sep).
IIA. Geophysical Activity Summary 25-2100Z to 26-2100Z
The geomagnetic
field has been at quiet to minor storm levels for the past 24 hours.
Solar wind speed reached a peak of 532 km/s at 26/1736Z. Total IMF
reached 18 nT at 25/2100Z. The maximum southward component of Bz reached
-12 nT at 26/1018Z. Electrons greater than 2 MeV at geosynchronous
orbit reached a peak level of 765 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on days one and three (27 Sep, 29 Sep)
and quiet to unsettled levels on day two (28 Sep). Protons have a slight
chance of crossing threshold on days one and two (27 Sep, 28 Sep) and
have a slight chance of crossing threshold on day three (29 Sep).
III. Event Probabilities 27 Sep to 29 Sep
| Class M | 40% | 45% | 35% |
| Class X | 15% | 15% | 10% |
| Proton | 15% | 15% | 10% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 26 Sep 165 Predicted 27 Sep-29 Sep 168/168/162 90 Day Mean 26 Sep 162
V. Geomagnetic A Indices
Observed Afr/Ap 25 Sep 015/021 Estimated Afr/Ap 26 Sep 026/033 Predicted Afr/Ap 27 Sep-29 Sep 011/012-007/008-009/012
VI. Geomagnetic Activity Probabilities 27 Sep to 29 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 20% |
| Minor storm | 10% | 05% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 20% | 25% |
| Major-severe storm | 30% | 20% | 30% |
All times in UTC
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